#define _CRT_SECURE_NO_WARNINGS 1
class Sum
{
public:
    Sum()
    {
        _sum += _num;
        _num++;
    }
    static int GetSum()
    {
        return _sum;
    }
private:
    static int _sum;
    static int _num;
};
int Sum::_sum = 0;
int Sum::_num = 1;
class Solution
{
public:
    int Sum_Solution(int n)
    {
        Sum a[n];
        return Sum::GetSum();
    }
};

